2-10 Phase Changes
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Warm-Up (summarize!!) Warm-Up (summarize!!) Water is an abundant substance on Earth. It can be found as a solid, a liquid, and as a gas called water vapor. 1. Write as many words you can think of to describe solid water? 2. Where is most of the liquid water on Earth found? Where is most of the water vapor found? 3. Describe a natural event you have observed when water changed from a liquid to a solid? When water changed from a liquid to a vapor?
Transcript of 2-10 Phase Changes
Warm-Up (summarize!!)Warm-Up (summarize!!)
Water is an abundant substance on Earth. It can be found as a solid, a liquid, and as a gas called water vapor.
1. Write as many words you can think of to describe solid water?
2. Where is most of the liquid water on Earth found? Where is most of the water vapor found?
3. Describe a natural event you have observed when water changed from a liquid to a solid? When water changed from a liquid to a vapor?
2-10 Phase Change2-10 Phase Change
• ObjectivesObjectives– DescribeDescribe phase change. phase change.– DescribeDescribe each of the six phase changes. each of the six phase changes.– ExplainExplain how temperature can be used how temperature can be used
to recognize a phase change.to recognize a phase change.– IdentifyIdentify phase changes as endothermic phase changes as endothermic
or exothermic.or exothermic.
Phase Changes – Changes of StatePhase Changes – Changes of State
• Adding or removing energy (heat) to Adding or removing energy (heat) to a substance causes phase changesa substance causes phase changes
• During a phase change, temperature During a phase change, temperature does does NOTNOT change change
• Phase changes are reversible.Phase changes are reversible.
Types of Phase changesTypes of Phase changes
• VaporizationVaporization– changing liquid into gas.changing liquid into gas.– evaporation and boiling.evaporation and boiling.– Adding energyAdding energy
•CondensationCondensation-changing gas into changing gas into
liquidliquid..-Removing energyRemoving energy
Types of Phase changesTypes of Phase changes
• SublimationSublimation– changing solid directly changing solid directly
into gas without into gas without becoming liquid.becoming liquid.
– Adding energyAdding energy
•DepositionDeposition-changing gas changing gas directly into solid.directly into solid.-Removing energyRemoving energy
Types of Phase changesTypes of Phase changes
• MeltingMelting– changing solid into changing solid into
liquid.liquid.– Adding energyAdding energy
• FreezingFreezing– changing liquid into changing liquid into
solid.solid.– Removing energyRemoving energy
AB
-heat Δ KE
-move faster
-temp. -solid
BC
-heat Δ PE
-get farther apart
-temp. stay same
-melting
CD
-heat Δ KE
-move faster
-temp. -liquid
Solid
Melting
Liqui
d
Phase Change Graps (T vs t)Phase Change Graps (T vs t)
DE
-heat Δ PE
-get farther apart
-temp. stay same
-boiling
EF
-heat Δ KE
-move faster
-temp.
-gas
Boiling Gas
Phase Change Graph (T vs t)Phase Change Graph (T vs t)
A
BC
DE
F
AB
-KE
-slows down
-temp.
-Gas
BC
-PE
-closer together
-temp. stays same
-Condensation
CD
-KE
-slows down
-temp.
-Liquid
Phase Change Graph (T vs t)Phase Change Graph (T vs t)
Energy FlowEnergy Flow
• Endothermic Endothermic – A change that is caused by absorbing A change that is caused by absorbing
energy from its surrounding.energy from its surrounding.– Melting, vaporizing, sublimingMelting, vaporizing, subliming
• ExothermicExothermic– A change is caused by releasing energy A change is caused by releasing energy
to the surroundings.to the surroundings.– Freezing, condensing, depositingFreezing, condensing, depositing
What is the boiling point?
What is the melting point?
What is the freezing point?
Boiling
Boiling Point
MeltingMelting Point
FreezingFreezing Point &
Phase Change Graph (T vs t)Phase Change Graph (T vs t)
